Weird science finds rainbows are a way to keep from blacking out

And it sends all of its important messages by fungus.

Good relationships with gays mean less binge drinking. Here's an unexpected way to keep heterosexual teens from binge drinking and passing out: start a gay-straight alliance in their school. A large study of Canadian teens (it followed over 21,000 of them) showed that schools that had policies or organizations that eased the integration of homosexuals into the student body had fewer problems with alcohol use, such as family troubles, blacking out, and getting into car accidents. This applied to almost all students; oddly, the exception were gay and bisexual boys, who saw little benefit.

Plants send messages on a fungus-net. We tend to think of plants as pretty static (well, aside from the whole "growing" thing), but they actually engage in a lot of chemical communication. They emit volatile compounds that can drive off predators, attract insects that eat what's eating the plant, or warn their fellow plants when they're being eaten. But what happens if the chemicals can't easily spread on the wind? Well, for those cases, the plants send their messages via a fungus-net.

The roots of many plants are associated with soil-dwelling fungi that can extend to the roots of neighboring plants. If a bean plant is attacked by aphids, its neighbors normally start producing compounds that ward off aphid attack. But, if you cut the fungal connections between them, the neighboring plants never gear up their defenses.

Submissive males are really girlie-men (in turkeys, at least). If your early years of schooling occurred in the US, then you undoubtedly did some drawings of a Thanksgiving-time turkey, with a bulging chest and large fan of feathers. That, it turns out, would be the dominant male. There are typically other males in a flock, but the submissive males don't develop many of the characteristics of the head male. Someone's now looked into what's going on at the level of gene expression and found that these submissive males look a bit female. In terms of the genes they express, the smaller males are clearly male, but there were a set of genes that were expressed at levels that are more similar to those seen in females. "Males with less manifestation of sexual dimorphism in phenotype were both demasculinized for male-biased genes, as well as feminized for female-biased genes," the researchers conclude. Lots of small changes seem to add up to a very different appearance.

Dogs find their owners boring. Well, probably not, but they are more likely to yawn at their owners. That's because yawns are socially contagious, meaning that, if we see someone else yawning, we're more likely to do so ourselves. This sort of social contagion appears to have deep evolutionary roots, as yawns can spread among other groups of mammals, including dogs. But dogs tend to bond socially with specific humans, and this apparently influences how easily social contagions can spread. Dogs will yawn along with just about anyone, but do so more often with people they have bonded with.

August is a fine month to kill off all your family members. Here's a happy bit of research: a grand survey of what are termed "family annihilators," or people who attempt to kill off all members of their immediate family. It's generally a male crime, with over 80 percent of the killers having a Y chromosome—but most violent crimes are committed by males, so that's not unexpected. What might be unexpected is that over 20 percent of the murders take place in August, and about half happen on weekends. The authors manage to make sense of that by noting that, in many cases, family problems that include loss of custody of the children trigger the murders. Often, the males only have custody of their kids on weekends and over school holidays, so that's when the killings are possible.